In recent years, in banks, large scale retail stores, and the like, many bills are handled every day, and there is a work for classifying and arranging these bills according to the nominal values and according to whether they are usable or damaged (i.e., according to the degree of damage and wear-out). When there are many bills, they are usually managed in such a manner that every 100 bills are strapped together. Therefore, a sheet arranging apparatus has been suggested as an apparatus for automating this kind of work for arranging bills. The bill processing apparatus includes a hopper unit for stacking and accommodating unclassified bills, a conveying mechanism for feeding and conveying the bills one by one therefrom, an inspection unit for distinguishing the type of a conveyed bill and the degree of damage of a conveyed bill, a plurality of pocket units for classifying and accumulating the distinguished bill on the basis of, e.g., nominal value, and a strapping unit for strapping every 100 bills accumulated, and the like.
For example, in finance institutions and the like, automatic teller machines (hereinafter referred to as ATMs) are widely available. The ATM automatically allows a client to, e.g., withdraw and transfer a transaction medium such as bills and coins. The number of ATMs installed are on the increase. The ATM includes an ATM cassette for accommodating bills serving as transaction media and a loading container such as a loading cassette. Bills are withdrawn from this loading container to a client. Alternatively, bills deposited by a client are accumulated in the loading container. In the ATM, it is necessary to refill and collect bills according to the situation of use. In this circumstance, a cash processing system has been suggested. The suggested cash processing system includes a loading container having a function of automatically refilling and collecting bills to/from a plurality of ATMs.
In the above cash processing system, it is necessary to separately prepare a loading container dedicated for refilling and recovering bills, which increases the cost. Moreover, each ATM needs to have a space for attaching the loading container, which increases the size of the ATM.
On the other hand, an apparatus for vertically stacking about 1000 sheets or less on a hopper unit at a time and performing pick up processing has been suggested. However, when more than 1000 sheets are stacked, the frictional force between the sheets increases due to the gravity of the stacked sheets. Therefore, when the sheets are picked up from the hopper unit, a separation force used in the frictional pick up process may be less than the frictional force between the sheets. As a result, the sheets may not be picked up in a stable manner, and this may cause problems of sheets such as slipping, two-sheets feeding, and multi-layered picking-up. In some cases, not only picked up sheets but also coins and foreign matters may be conveyed together. When they are conveyed to the inspection unit, the inspection unit may be damaged.